点刺皮肤试验阳性对照液浓度的研究

Concentration of histamine for use as a positive control of prick skin testing

目的为了提高皮肤点刺试验质量,笔者对皮肤点刺试验的阳性对照液的浓度进行了研究。方法均为门诊患者,皮试前停用抗组胺药,所用阳性对照液的浓度分别为54.3 mmol/L(简称高浓度)和5.43 mmol/L(简称低浓度),应用常规的方法进行点刺,10 min后判读。本试验分两阶段进行,第一阶段分别行高、低浓度组胺的点刺试验。第一阶段试验40例,风团面积分别为:(18±8)mm^2和(28±14)mm^2,几何均值分别为15 mm^2和24mm^2,红斑分别为(234±122)mm^2和(586±226)mm^2;几何均值分别为:216 mm^2和524 mm^2,高浓度的风团和红斑面积明显高于低浓度;第二阶段,在第一阶段试验基础上,加做高浓度点刺试验。结果第二阶段70例,高浓度点刺风团面积均值为:(30±19)mm^2;几何均值为:26 mm^2。红斑面积为(661±342)mm^2;几何均值分别为:571mm^2。所有病例点刺后均迅速出现瘙痒,10 min后风团和红晕达到最大值,20～30 min后自行消退,均未出现全身不良反应。结论(1)本试验提示在过敏原皮肤试验时必需加做阳性对照和阴性对照;(2)如有条件,可应用高低两个浓度同时进行阳性对照,以显示组胺浓度与皮肤反应的量效关系,使对照试验更为可靠;(3)皮肤试验的风团和红斑具有相同的意义。

Objective To study the concentration of histamine for use as a positive control of the prick skin testing. Methods All subjects were outpatients who did not take antihistamines before the test. The concentrations of positive controls were 54.3mmol/ L and 5.43mmol/L, separately. After 10 minutes, the results were obtained. Results The study consisted of two stages. The number of subjects in the first stage was 40. The histamine in high and low concentrations was used. The mean wheal sizes were 18 ± 8 mm^2 and 28 ± 14 mm^2 ,geometric means were 15 mm^2 and 24 mm^2 ,the flare sizes were 234 ± 122 mm^2 and 586 ± 226 mm^2, geometric means were 216 mm^2 and 524 mm^2, respectively. The wheal and flare sizes of the histamine in higher concentration exceeded the lower obviously. On the second stage, 70 subjects were added, the mean wheal size of high concentration was 30 ± 19 mm^2 and geometric mean was 571 mm^2. All the patients felt pruritus immediately after prick testing, whose wheal and flare sizes reached the maximum after 10 minutes and subsided after 20 - 30 minutes without adverse reactions of the whole body. Conclusion 1. The test showed that the positive and negative control of the prick skin testing were necessary to the allergen test. 2. The positive control test would be more reliable, if different concentration was used to show dose - response relationship. 3. The wheals and flares of skin test were both important.